Insulation connector for use with electrical jack and plug structures



Get. 24, 1961 R. c. KOCH 3,005,972

INSULATION CONNECTOR FOR usE WITH ELECTRICAL v JACK AND PLUG STRUCTURES Filed April 14, 1958 INVENTOR. RICHARD C. KOCH ATTORNEY 3,M5,7Z Patented Get. 24, 1961 3,605,972 E ISULATIQN CGNNECTGR FUR USE WITH ELEC- TRICAL JACK AND PLUG STRUCTURES Richard C. Koch, 5579 E. Lehigh Ave, Denver, Colo. Filed Apr. 14, 1958, Ser. No. 728,478 2 Claims. ((11.339-101) This invention relates to an improved electrical connector means and more specifically to an improved insulating connector means particularly useful in providing among other things strain relief and longer life for a Wire-like conductor electrically connectable to an electrical plug or jack structure through a side entry thereof. Reference is hereby made to my United States Patent No. 2,713,670 granted July 19, 1955, and entitled Electrical Jack, my United States Patent No. 2,851,669 granted Sept. 9, 1958, entitled Expansion Type Connector Plug and my co-pending US. application Serial No. 728,477 filed April 14, 1958, and entitled Electrical Jack, and filed concurrently herewith, the present invention being readily usable in combinaiton therewith and constituting an improvement thereover for reasons that will become apparent hereinafter.

In prior art jack and particularly plug structures, to the best of my knowledge, it has been difiicult to connect, without substantial strain being imposed thereto, an additional electrical conductor to such a structure through a side entry port thereof and at the same time provide a fully insulated connection that results in long life of the conductor. Generally the conductor takes the form of a wire and due to flexing action and the like, particularly from side wire pull, there is substantial strain imposed which often results in early breakage.

It is the primary object of this invention to provide an improved connection means for use in elfecting strain relief, longer life and improved insulation of such an additional electrical conductor.

Another object of the invention is to provide an insulation connector of the type described in the preceding paragraph wherein there is provided a collar adapted to be mounted on the jack or plug structure adjacent the point of connection of the electrical conductor thereto, and a tubular portion depending from the collar adapted to receive the electrical conductor in insulating and strain relief fashion.

A further object of the invention is to provide an insulation connector of the type described above which may be mounted on most any plug or jack structure of the type adapted to receive an electrical connector through an opening or side entry generally transverse to the main axis of the structure.

A still further object of the invention is to provide an improved insulation connector of the type described above which in addition to all other advantages provides relief from the usual side bending and flexing strain on the electrical connector that is evident with prior art connections of such wire connectors.

Other objects and advantages of the present invention will become apparent from the following detailed description taken in conjunction with the accompanying drawing where a preferred embodiment is illustrated and wherein:

FIGURE 1 is an enlarged longitudinal view partly in section of an electrical plug structure including the insulation connector of this invention, said plug being shown attached to a jack secured to a panel and having an electrical conductor connected thereto on the forward side of the panel;

FIGURE 2 is an enlarged longitudinal view partly in section and similar to that of FIGURE 1 but taken, insofar as the sectional part is concerned, on a vertical plane at substantially 90 degrees to the plane of FIGURE 1 and with an additional plug shown in dotted lines inserted therein but omitting the jack and panel of FIGURE 1; and

FIGURE 3 is a View taken along line 33 of FIG- URE 2.

Perhaps it should be stated at the outset that the invention is not limited in its application to use with the particular plug structure shown in the drawing and the phaseology and terminology employed herein is for the purpose of description and not limitation.

Referring to FIGURE 1 of the drawing, there is disclosed a panel P having an aperture It) whereby an electrical jack, such as the type illustrated in FIGURE 1 of said patent No. 2,713,670 and generally shown at J, may be attached to the panel. Numeral 11 represents an elongated cylindrical body or member of suitable electrical conducting material having on one end thereof a plug portion 12 of reduced diameter adapted to mate electrically with jack J. The elongated member at its opposite end is provided With an axial bore or socket 13 having an internal diameter substantially equal to the diameter of the plug portion 12, thus forming with portion 11 a receptacle adapted to receive another electrical plug B, such as of the banana type, in electrical contacting relation. In actuality, illustrated unit 11 is a jack plug combination in the sense that socket 1'3 is provided for receiving an additional plug B and reference in some instances in the specification and claims will be made to this terminology. However, it will become apparent that the essence of this invention resides in the collar C for use with a jack plug combination as shown, or merely a plug similar to 11 without socket 13 or strain relief use with conductor W of my application being filed concurrently herewith or genreally for use with most any jack or plug structure of the type adapted to electrically receive an electrical conductor generally in the form of a cone. Usually, the coupling C will be associated with aside opening or side entry having an axis transverse to themain axis of the plug or jack structure and although the coupling will as a general rule be supported on the exterior of such structure, it is within the scope of this invention to position the section 23 of the coupling inte'rior of the structure.

There is provided an axial bore 14- at the bottom of bore 13 of lesser diameter and threaded to receive screw 15. A third bore 16 is provided in elongated member 11 normal to axial bore 14 to intersect the lower portion of bore 14 at a point intermediate the bottom of bore 13 and plug portion 12. Bore 16 may conveniently be provided with a counter bore 17 of slightly greater diameter adjacent the surface of elongated member 11 and extending into a portion of the length of bore 16 for the purpose to be described. Screw 15 is of a length such that when the screw is completely seated the end thereof projects slightly into bore 16 as shown in FIGURE 2.

The surface of elongated member 1 1 along a portion of its length is provided with a knurling 18. A cylindrical, tubular member 19 of a suitable insulating material having an internal diameter substantially equal to the diameter of member 11 is press-fit thereover and held in place by the knurling I8. Tubular member 19 is preferably of a length to extend from just short of the plug portion 12 to a point beyond the opposite end of elongated member 11. The end of tubular member 19 opposite plug 12 is provided with a counter bore 25 slightly greater than the internal diameter of member '19 and ex tending slightly into elongated member 11. Tubular member 19 is also provided with a bore 20 in the Wall thereof in registry with counter bore 17 and of substantially the same diameter, the combined bores 16, 17 and ape-5,972

20 forming a side opening or entry transverse to the main axis of unit 11.

In use, a suitable electrical wire conductor 21 having a portion of its insulation 22 cut away from the end is inserted into bore 16 through the said side entry, and screw 15 is tightened thereon to efiect the electrical connection. Counter bore 1'7 is of a diameter to receive insulation 21 when desired. Since the diameter of insulation member 19 is usually of a minor dimension, the amount of insulation 22 on conductor 21 that can be stripped away is rather critical to avoid exposure of the uninsulated conductor. Further, the length of conductor 21 held within the plug connection is relatively short and the conductor is subjected to rather severe bending stress and strain, particularly side pull, which may result in the conductor failing physically at an early life and thus eiectrically. To avoid these undesirable results, applicant has provided an insulation connection or strain relief member generally designated by C of suitable insulation material comprising a large tubular portion 23 having an internal diameter of a dimension such that tubular portion 23 may be press-fit mounted on insulation member 19 and positioned to overlie bore 16 and counter bore 17. Connector C further includes a smaller tubular portion 24 depending 'from tubular portion 23 with its axis normal to the axis of tube 23 and communicating therewith in registry with said side entry including bore 20 of insulation member 19 and counter bore 17 of longitudinal member 11. In certain instances it may be desirable that insulation connector C be permanently attached to the jack as by cementing and the like, although a press-fit mounting is usually entirely satisfactory.

It will be noted that with the insulation connector C of this invention mounted on the plug, that even when the insulation 22 is stripped beyond the normal insulation 19 of the jack that tubular portion 24 provides complete and adequate insulation for the bared conductor 21. Further, the tubular member 24 is preferably of such length to remove the bending point of conductor 21 a sufficient distance away from the contacting point of screw 15 with the conductor to relieve flexing bending stress on the connection and avoid physical failure and thus result in longer life of conductor 21. 7

While there has been described what at present is considered to be the preferred embodiment of this invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention. It is aimed, therefore, in

i the appended claims to cover all such changes and modifications which fall within the true spirit and scope of the invention.

What is claimed is:

1. In combination, an electrical jack-plug structure including an elongate cylindrical body and an outer concentric elongate tubular member of frictional insulating material having an internal diameter equal to the diameter of said body for mounting in press-fit relation on said body with a bore passing through said elongate tubular member and said body normal to the longitudinal axes thereof for receiving an electrical wirelike conductor, and means in said body to engage said conductor for holding said conductor in electrical contact with said body: and an insulation connector composed of frictional insulating material including a first tubular member defined by a collar of limited length in relation to said elongate tubular member having an internal diameter equal to the outer diameter of said elongate tubular member for mounting in outer concentric, press-fit relation on said elongate tubular member in a position overlying the bore, and a second tubular member integrally formed with said collar and extending radially and outwardly there- 'from perpendicular to the axis' thereof, the opening formed by said second tubular member extending through said first tubular member for registry with the bore in said elongate tubular member and said cylindrical body whereby the opening and bore are aligned to receive the conductor.

2. The combination according to claim 1 wherein said second tubular member is relatively long in relation to the length of said collar and is further characterized by being of a rigidity sufficient to provide substantial removal of the bending point of said conductor from the point of connection with said electrical jack-plug structure to relieve substantially all bending stress from the connection between said conductor and said jack-plug structure.

References Cited in the file of this patent UNITED STATES PATENTS 1,139,973 Herz May 18, 1915 1,731,661 Hauenstein Oct. 15, 1929 2,279,341 Powell Apr. 14, 1942 2,446,007 Hook July 27, 1948 2,657,370 Hobson Oct. 27, 1953 2,713,670 Koch July 19, 1955 2,851,669 Koch Sept. 9, 1958 

